Exhaust muffler



June 20, 1961 J. D. REESE 2,989,138

EXHAUST MUFFLER Filed Dec. 29, 1958 3 4 FIG. I

INVENTOR. JAMES D. RE SE Byzgigdrl magi ATTORNEYSV United States Patent 2,989,138 EXHAUST MUFFLER James D. Reese, 18 W. Crosier, Akron 11, Ohio Filed Dec. 29, 1958, Ser. No. 783,351 4 Claims. (Cl. 181-50) The present invention relates to an exhaust muffler. More particularly, the invention relates to an improved mufller construction for receiving expanding and noise producing exhaust gases such as are discharged from internal combustion engines.

The problems encountered in the construction of a satisfactory exhaust mufiler are many. The mufiier should silence to a barely audible level gases which are pulsatingly discharged under high pressure; the exhaust gases should be cooled; solid combustion products, particularly those of organic composition, should largely be retained within the muffler and not discharged to contaminate the atmosphere; and, the muffier should be long-lived and not require frequent replacement as is now often the case. A satisfactory mufiler should attain each of these objects and yet be of low cost and economical construction.

\The general object of the present invention is to provide an exhaust muffler of novel construction which is superior to presently available mufllers in the aforementioned respect. The concept of the invention will be understood by reference to the detailed description and the attached drawing.

In the drawing:

FIG. 1 is a top plan view of a muffler according to the invention;

FIG. 2 is a corner section taken substantially as indicated on line 22 of FIG. 1;

FIG. 3 is an end view taken substantially as indicated on line 3-3 of FIG. 1;

FIG. 4 is a cross-section taken substantially as indicated on line 44 of FIG. 1;

FIG. 5 is a corner section, similar to FIG. 2, showing a modified mufiler construction according to the invention; and,

FIG. 6 is a cross-section, similar to FIG. 4, taken substantially as indicated on line 6-6 of FIG. 5.

The exhaust mufiler, indicated generally by the numeral 10, includes an elongated outer housing or casing 12, closed by front and rear end walls, 14 and 15 respectively. The interior construction of the muffler 10 is such that heat transfer to the outer surface of casing 12 is minimized. Further, the end walls 14 and 15 may be vented as at 14a and 15a for release of heat trapped therein. Accordingly, the housing 12 may be fabricated of a light gauge sheet metal which provides for light-weight construction. :It will further be noted that use of a light gauge metal for the housing and end walls permits the mechanical formation of a crimp or overlap joint, as indicated at 16, rather than the welded or riveted joint of conventional mufiler constructions.

Within the muffler 10 are two parallel ducts 18 and 19. 'Each duct is square, rather than round as in conventional mufller construction, and is fabrictaed of a corrosion-resistant material such as stainless steel. It has been found that forming each duct 18 and 19 in square-shape provides for eflfective transfer of the heat in the exhaust gases and also permits retention of harmful combustion products, such as tars, within the muffler.

Duct 18 is provided with an inlet tube 20 which is preferably bent or angled to pass through the midpoint of the end wall 14. The outer end of tube 20 is preferably slotted as at 21 for ease of connection to an exhaust pipe running from the engine manifold (not shown). The opposite end of duct 18 is closed as by a plate 22.

The parallel duct 19 is closed by a similar plate 23 and is provided with a preferably straight outlet tube 24 passing through the end wall 15. The outer end of tube 24 is also preferably slotted as at 21' for connection to an exhaust pipe running to an exhaust resonator or the rear of the vehicle chassis (not shown).

The parallel ducts 18 and 19 are connected or in communication by a series of smaller diameter manifold ducts 25. In the preferred embodiment of the invention, there are preferably four manifold ducts 25 which are square/shape and also preferably fabricated of a corrosion-resistant material.

As shown in FIGS. 1 and 4, each manifold duct 25 extends between the outer wall 18a of the entry duct to the outer wall 19a of the exit duct. Each duct 25 is preferably secured in place by welds against the inner walls, 18b and 19b, of the entry and exit ducts. The portion of each manifold duct 25 enclosed within the ducts 18 and 19 is provided on front and rear walls with a series of regularly spaced passages 26. Preferably, the passages are square-shape with five passages on each front and rear wall of each end of a'manifold duct 25. Thus, as shown, the end of a manifold duct 25 within the inlet duct 18 has five inlet and five outlet passages 26. The end of a duct 25 within the outlet duct 19 also has five passages 26 on each side.

In the alternative form of muffler 10 as illustrated in FIGS. 5 and 6, the manifold ducts are tubes 28 and are also preferably four in number and secured in place similarly to the square manifold ducts 25. Each end of each manifold tube 28 has a series, preferably ten, passages 29. It will be noted that whereas the square manifold ducts 25 rest on the bottom wall of each tube 18 and 19, the round manifold tubes 28 preferably are between the top and bottom wall of each tube 18 and 19. This construction is preferred for use with larger engines or for handling exhaust gases under very high pressure.

The exact number of passages 26 or 29 in each manifold 25 or 28 is not critical for long as suflicient passages are afforded to pass through without hinderance about half of the exhaust gas from inlet tube 20 while baflling or diverting the remainder. As illustrated by the arrows in FIGS. 1 and 2 or FIG. 5, the main stream of the exhaust gas entering duct 18 is bafiled into a plurality of smaller streams moving in divergent or different directions.

The construction of mutfier 10 is completed by inserting the several components described above into the casing 12 with end wall 15 attached, and fully packing the interior of the casing 12 with an insulation material indicated at 30. The insulation material 30 is preferably a pulverent or granulated material such as mineral wool or asbestos particles which can be forced in between the ducts 18 and 19 and manifolds 25 or 28, as well as against the casing 12. After the insulation is completely packed, the end wall 14 is attached to the casing as at 16 and the mufller 10 is ready for use.

As has now been described, it will be apparent that with the novel mufiler 10 a satisfactory noise level can be attained. The many bafile surfaces of the manifolds 25 or 28 and the tightly packed insulation 30 will diffuse and absorb the sound waves. The same baffle surfaces, the large surfaces afforded by the square rather than round ducts 18 and 19 and the insulation material will also deprive the exhaust gas of its heat energy. It has actually been found with a mufiler constructed according to FIG. 1, and installed on a passenger vehicle that the casing 12 is just barely warm to the touch and that the exhaust gases from outlet 24 are relatively cool.

It will also now be apparent that the square-shape of ducts 18 and 19 will afford condensation or collecting surfaces for large amounts of harmful combustion products which would otherwise be exhausted to atmosphere. Such products are believed to be an important source of atmospheric contamination. It is considered that a muffler can collect large amounts of such particles, individually microscopic in size, without requiring replacement.

Lastly, it is apparent that the novel muffler 10 will be so long-lived and so easily fabricated that the overall result willbe a lower mulfler cost.

What is claimed is:

1. An exhaust mufller comprising, a housing having end walls, two parallel square ducts, each closed at one end within said housing, an inlet tube extending through one of said end walls connected to the open end of one of said parallel ducts, an outlet tube extending through the other of said end Walls and connected to the open end of the other of said parallel ducts, a plurality of manifold ducts extending across and between said parallel ducts, the portion of each manifold duct extending across said parallel ducts having a series of passages communicating with said parallel ducts, and insulation material packed between said casing and end walls and parallel ducts and manifod ducts.

2. An exhaust muffier comprising, a light gauge metal casing having vented end walls crimped thereto, two parallel square corrosion resistant ducts each closed at one-end within said housing, an inlet tube extending through one of said end walls and connected to the open end of one of said parallel ducts, an outlet tube extending through the other of said end walls and connected to the open end of the other of said parallel ducts, a plurality of corrosion resistant manifold ducts extending wall to Wall within and between said parallel ducts, the wall to wall portion of each manifold duct having a series of l 4 passages communicating with said parallel ducts, and in sulation material packed between said casing and end walls and parallel ducts and manifold ducts.

3. An exhaust rnufller comprising an elongated housing, two parallel square ducts within said housing, a plurality of square manifold ducts extending wall to wall within and between said parallel ducts, the portions of each manifold duct within said parallel ducts having a series of pass-ages communicating with said square ducts.

4. An exhaust mufller comprising a casing having vented end walls, two parallel square ducts each closed at one end within said housing, an inlet tube extending through one of said end walls and connected to the open end of one of said parallel ducts, an outlet tube extending through the other of said end walls and connected to the open end of the other of said parallel ducts, a plurality of manifold ducts extending wall to wall within and between said parallel ducts, the wall to Wall portion of each manifold duct having a series of passages communicating with said paralel ducts, and insulation material packed between said casing and end walls and parallel ducts and manifold ducts.

References Cited in the file of this patent UNITED STATES PATENTS 1,009,216

. UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent NO. 2,989 138 June 20 1961 James D, Reese It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2 line 4O for "for long" read so long Signed and sealed this 19th day of December 1961.

( SEA L) Attest:

ERNEST W. SWIDER DAVID L. LADD Commissioner of Patents Attesting Officer USCOMM-DC UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 2 989 138 June 20 1961 James Du, Reese It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2 line 40,, for "for long" read so long --b Signed and sealed this 19th day of December 1961;

(SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Commissioner of Patents Attesting Officer U SCO M M DC 

